Resistance switching characteristics and mechanisms of MXene/SiO2 structure-based memristor

Silicon dioxide memristors possess multiple resistance states and can be used as a key component of memory devices and neuromorphic systems. However, their conductive mechanisms are incompletely understood, and their resistance switching (RS) variability is a major challenge for commercialization of memristors. In this work, by combining the desirable properties of silicon dioxide with those of a two-dimensional MXene material (Ti3C2), a memristor based on an MXene/SiO2 structure is fabricated. The Cu/MXene/SiO2/W memristive devices exhibit excellent switching performance compared with traditional Cu/SiO2/W devices under the same conditions. Furthermore, the role of the MXene/SiO2 structure in the SiO2-based memristors is revealed by the physical characterization of the MXene and first-principles calculation of the MXene/SiO2 structure. The results indicate that the conductive filaments (CFs) are more likely to grow along the locations of MXene nanostructures, which reduces the randomness of CFs in the Cu/MXene/SiO2/W memristors and further improves the device performance. Meanwhile, the MXene/SiO2 structure appears to greatly reduce the mobility of Cu ions in the entire RS region, as well as improve the performance of the SiO2-based memristors while maintaining the operating voltages low.